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Micro-review of structure functions and parton distribution functions

Description: There has recently been a great deal of discussion concerning the surprising differences in the measurements of the nucleon structure function F/sub 2/(x,Q/sup 2/), off of a hydrogen target, by the high statistics muoproduction experiments EMC and BCDMS. In this short review I will attempt to summarize the status of the experimental measurements of the structure functions and highlight any significant disagreements. At the conclusion I will comment on the status of the extraction of the parton distribution functions from these measurements. 17 refs., 16 figs., 2 tabs.
Date: January 1, 1989
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

Survey of nu/sub. mu. /e physics with emphasis on recent Fermilab results

Description: From both an experimental and an historical point of view it is particularly appropriate to summarize the development of nu/sub ..mu../e/sup -/ physics at this time. Historically, it was ten years ago last week that the announcement of the first nu/sub ..mu../e/sup -/ event was sent from Aachen to the other members of the Gargamelle Collaboration. The event, shown in Figure 2, is of a single electron identified via its characteristic bremsstrahlung and curvature. The significance of this event far exceeds its visual impact. With a background of less than .03 events, it became the first solid indication for the existence of the weak neutral current. On the experimental front, the investigation of the nu/sub ..mu../e interaction is about to enter a new phase, having graduated from experiments yielding 2 to 3 events to those which will be analyzing hundreds of events. With these high statistics experiments it should be possible to study the differential as well as the total crosssections of nu/sub ..mu../e and anti nu/sub ..mu../e scattering.
Date: June 1, 1983
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

Contribution of twist-4 to the Q/sup 2/ evolution of F/sub 2/ and xF/sub 3/: an experimental review

Description: The status of the theoretical and experimental study of higher twist contributions to the nucleon structure functions is reviewed. After noting the dangers of combining experiments with widely different <Q/sup 2/> and targets, emphasis is placed on those results coming from a single experiment. The values of ..lambda.., the twist-2 scale factor, and h/sub 4/, the coefficient of x/Q/sup 2/(1-x), are restricted by: ..lambda.. <0.44 GeV and -0.2 <h/sub 4/<0.5 GeV/sup 2/.
Date: November 1, 1982
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

A global analysis of recent experimental results: How well determined are the parton distribution functions

Description: Following is a brief summary of the results of an analysis of experimental data performed to extract the patron distribution functions. In contrast to other global analyses, this study investigated how the fit results depend on: Experimental Systematic Errors; Kinematic Cuts on the Analyzed Data and Choice of Initial Functional Forms, with a prime goal being a close look at the range of low-x behavior allowed by data. This is crucial for predictions for the SSC/LHC, HERA, and even at Tevatron Collider energies. Since all details can be found in the just released Fermilab preprint Parton Distributions from a Global QCD Analysis of Deep Inelastic Scattering and Lepton-Pair Production by J. G. M. and Wu-Ki Tung, this summary will be only a brief outline of major results. 11 refs., 13 figs.
Date: August 1, 1990
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

Neutrino scattering physics and experiments at super beams and neutrino factories

Description: A careful study of neutrino scattering physics is an essential part of the program to answer many open questions being addressed by several different physics communities. A deeper understanding of nuclear effects induced by neutrinos and considerably more accurate measurements of neutrino exclusive cross sections is crucial for minimizing systematics of neutrino oscillation experiments. In addition, the knowledge gained by neutrino scattering experiments is important to the Nuclear Physics and Astro-Particle physics communities as well. A review of where we expect to be in the study of neutrino scattering physics at the start of a Super Neutrino Beam Facility as well as the types of beams and detectors needed at such a facility are discussed.
Date: January 1, 2006
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

Using neutrinos as a probe of the strong interaction

Description: Neutrino scattering experiments have been studying QCD for over 30 years. From the Gargamelle experiments in the early 70's, through the subsequent bubble chamber and electronic detector experiments in the 80's and 90's, neutrino scattering experiments have steadily accumulated increasing statistics and minimized their systematic errors. While the most recent study of QCD with neutrinos is from the TeVatron neutrino beam (the NuTeV experiment with results presented by Martin Tzanov at this Workshop), near-future studies will shift to the Main Injector based NuMI facility also at Fermilab. The NuMI Facility at Fermilab provides an extremely intense beam of neutrinos making it an ideal place for high statistics (anti)neutrino-nucleon/nucleus scattering experiments. The MINERvA experiment at Fermilab is a collaboration of elementary-particle and nuclear physicists planning to use a fully active fine-grained solid scintillator detector to measure absolute exclusive cross-sections and nuclear effects in v - A interactions as well as a systematic study of the resonance-DIS transition region and DIS with an emphasis on the extraction of high-xBj parton distribution functions. Further in the future an intense proton source, the Fermilab Proton Driver, will increase neutrino interaction rates by a further factor of 5-20.
Date: January 1, 2005
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

A high-statistics study of low-energy neutrino-nucleus scattering in the NuMI beam at Fermilab

Description: The NuMI Facility at Fermilab is providing an extremely intense beam of neutrinos for the MINOS Neutrino Oscillation Experiment. It an ideal place for a high statistics (anti)neutrino-nucleon/nucleus scattering experiments, and the MINER{nu}A experiment, a collaboration of elementary-particle and nuclear physicists, is planning to install a fully active fine-grained solid scintillator detector in this beam. The overall goals of the experiment are to measure absolute exclusive cross-sections, study nuclear effects in {nu} - A interactions and perform a systematic study of the resonance-DIS transition region including the extraction of high-x Bj parton distribution functions at low Q2.
Date: January 1, 2006
Creator: Morfin, J.G.
Partner: UNT Libraries Government Documents Department

Method to rapidly tune the halo spoilers of the tevatron muon beam

Description: An active shield has been constructed which forms a sharp magnetic edge around the central core of useful muons and sweeps the envelope of halo muons (those that enter the aperture of an experiment without having passed through the momentum tagging system) radially away from beam center. Two types of halo scrapers have been employed in this shield: conventional toroidal magnets and a newly developed magnetic element called ''mupipe''. The mupipes have eight degrees of motion, so attempting to tune the mupipe system by systematic measurements over the full range of each coordinate would be impractical. An algorithm was formulated to take a small set of measured values and from them predict the required positions of the two sections of mupipe to obtain maximum beam and minimum halo. The algorithm measures the muon and halo yields at a representative subset of coordinated, employs a fitting program to find a functional form for the yields in terms of the coorinated, and maximizes that function in terms of the coordinates. The algorithm was tested by applying a Monte Carlo program to predict the halo and muon yield for a given orientation of the two movable sections of mupipe. (LEW)
Date: September 1, 1986
Creator: Ojeda, Y.; Scott, B.; Malensek, A. & Morfin, J.G.
Partner: UNT Libraries Government Documents Department

Proposal to perform a high - statisics neutrino scattering experiment using a fine - grained detector in the NuMI Beam

Description: The NuMI facility at Fermilab will provide an extremely intense beam of neutrinos for the MINOS neutrino-oscillation experiment. The spacious and fully-outfitted MINOS near detector hall will be the ideal venue for a high-statistics, high-resolution {nu} and {bar {nu}}-nucleon/nucleus scattering experiment. The experiment described here will measure neutrino cross-sections and probe nuclear effects essential to present and future neutrino-oscillation experiments. Moreover, with the high NuMI beam intensity, the experiment will either initially address or significantly improve our knowledge of a wide variety of neutrino physics topics of interest and importance to the elementary-particle and nuclear-physics communities.
Date: December 1, 2003
Creator: Morfin, J.G.; /Fermilab; McFarland, K. & U., /Rochester
Partner: UNT Libraries Government Documents Department

''Econodump'' design for the Fermilab Direct Neutral Lepton Facility

Description: An extensive effort has been directed toward a major redesign of the Fermilab Direct Neutral Lepton Facility (DNLF). The goal has been a very significant cost reduction of the facility, with minimal sacrifice of physics potential. Hence the name ''Econodump'' applied to the redesign effort.
Date: August 1, 1986
Creator: Childress, S.; Brown, C.; Koizumi, G.; Malensek, A.; Morfin, J.G.; Murphy, T. et al.
Partner: UNT Libraries Government Documents Department

Determination of the nucleon structure using the weak neutral current

Description: An experimental determination of the neutral current structure functions of the nucleon is obtained by measuring the ratio of the neutral current x distribution to the charged current x distribution. The analysis is based on deep inelastic neutrino nucleon scattering data gathered in a massive fine-grained neutrino detector exposed to a narrow band neutrino beam at Fermilab. 12 refs., 2 figs., 2 tabs.
Date: July 1, 1985
Creator: Bogert, D.; Burnstein, R.; Fisk, R.; Fuess, S.; Morfin, J.G.; Ohska, T. et al.
Partner: UNT Libraries Government Documents Department

The Impact of new neutrino DIS and Drell-Yan data on large-x parton distributions

Description: New data sets have recently become available for neutrino and antineutrino deep inelastic scattering on nuclear targets and for inclusive dimuon production in pp and pd interactions. These data sets are sensitive to different combinations of parton distribution functions in the large-x region and, therefore, provide different constraints when incorporated into global parton distribution function fits. We compare and contrast the effects of these new data on parton distribution fits, with special emphasis on the effects at large x. The effects of the use of nuclear targets in the neutrino and antineutrino data sets are also investigated.
Date: February 1, 2007
Creator: Owens, J.F.; U., /Florida State; Huston, J.; U., /Michigan State; Keppel, C.E.; Lab, /Hampton U. /Jefferson et al.
Partner: UNT Libraries Government Documents Department

Renaissance of the ~ 1-TeV Fixed-Target Program

Description: This document describes the physics potential of a new fixed-target program based on a {approx}1 TeV proton source. Two proton sources are potentially available in the future: the existing Tevatron at Fermilab, which can provide 800 GeV protons for fixed-target physics, and a possible upgrade to the SPS at CERN, called SPS+, which would produce 1 TeV protons on target. In this paper we use an example Tevatron fixed-target program to illustrate the high discovery potential possible in the charm and neutrino sectors. We highlight examples which are either unique to the program or difficult to accomplish at other venues.
Date: December 2, 2011
Creator: Adams, T.; U., /Florida State; Appel, J.A.; /Fermilab; Arms, K.E.; U., /Minnesota et al.
Partner: UNT Libraries Government Documents Department